Glyn Barnes
Just been listening to Beardfish, Rikard Sjöblom's keyboard playing is exceptional. I knew him primarily from his guitar (and occasional) keyboard work with Big Big Train, but did not realise quite how good he is on keys.

 
His playing on Judas Unrepentant on the Merchants of Light album is incredible, sounds like he has 7 fingers on each hand.
 
I bought his last Gungfly album recently. Great instrumentally, but vocally/lyrically it's pretty poor. I was really disappointed, glad I downloaded it rather than buying the CD.
 
 

bitflipperMore important is what the keyboard player adds to the song and to the band. Rick Wright embodies that ideal, and that's someone I can listen to for hours.

 
Case in point: David Gilmour's Live in Gdansk.  Wright played on that album and the interplay between the two at the end of "Echoes" was just sublime.
 

For many years my vote would have gone to Wakeman, but I still think Emerson tops him in all the important areas - composition, technique, flair
 
The piano parts of the first 2 sections of the title track from Trilogy still leave me with goosebumps every time I hear it.

Well. Prog magazine's results are out. They have published the top 50, which I am not going to type out here. But here is the top 10
 
1 Keith Emerson
2 Rick Wakeman
3 Tony Banks
4 Richard Wright
5 Jordan Rudess
6 Mark Kelly
7 Patric Moraz
8 Geoff Downes
9 Derek Sherinian
10 Jon Lord
 
Of the newer artists the terrifically talented Russian Gleb Kolyadin makes it to 15, how well would he have done without the nostalgia element? At 29 he is the youngest in the list.
 
Geddy Lee is no 19!
 
Some other favorites of mine
21 Martin Orford
24 Dave Greenslade
31 Danny Manners
34 Vincent Crane
 
There are some interesting stat at the end of the article. By sales (solo and with bands) the top three would be 1 Richard Wright, 2 Tony Banks, 3 Rick Wakeman (I wonder if this includes Wakeman's session work?)
 
52% British, 22% USA. 4% Canada.
 
70% had first appeared on record before 1980 and only 6% since 2000, this probably says as much about the voting demographic as anything else.
 
 
 
 
 

A really underrated keyboardist is Lasse Finbråten from Circus Maximus.
 
He is not the “best”, but Circus Maximus is just a hobby project because of low income of the music, and he is still giving this much effort is giving him a big star.
 
And the guy just enjoys playing live.
 

70% had first appeared on record before 1980 and only 6% since 2000, this probably says as much about the voting demographic as anything else.

Another possible factor...
 
8 years ago Prog Magazine said Rudess was #1. Since then, two of the four guys above him on today's list have died. Jordan just needs to kick the bucket to reclaim the top spot. 

Interestingly Rudess was a guest on Gleb Koyladen's solo album, so 2 of the top 15 on one album! Gleb is primarily a piano player, so Rudess did other keyboards on some tracks.

Following the success of two highly-praised albums with Iamthemorning, Russian virtuoso pianist Gleb Kolyadin affirms his musical authority with his debut, self-titled album on Kscope. The record features a staggering who’s-who of performers, including: Gavin Harrison (King Crimson / Porcupine Tree) on drums; Nick Beggs (Steven Wilson) on bass; Theo Travis (Robert Fripp / Porcupine Tree / Steven Wilson) on flute and saxophone; the unmistakable voice and lyrics of Steve Hogarth (Marillion) alongside Mick Moss (Antimatter); and Jordan Rudess (Dream Theater) on additional keys.”the single greatest pianist I’ve ever met in my life.” Daniel Cavanagh (Anathema).

Some videos etc. here http://www.kscopemusic.com/artists/gleb-kolyadin/